rust-dirstate-status: add call to rust-fast path for `dirstate.status`
The reasoning behind this patch is explained in the first patch of the series.
Differential Revision: https://phab.mercurial-scm.org/D7060
pager.pager=p0 # $TESTTMP/sysrc:4
ui.editor=e1 # $TESTTMP/userrc:2
pager.pager=p2 # $PAGER
ui.editor=e1 # $TESTTMP/userrc:2